This bug has been reported as Launchpad Bug 1218547 - Clevo W350ST brightness keys don't work on Kubuntu and was requested to report to upstream. The Fn+F8 and Fn+F9 keys are not working on my Clevo W350ST with Kubuntu Raring to change screen brightness of the internal laptop screen. I installed linux-headers-3.11.0-4, linux-headers-3.11.0-4-generic, linux-image-3.11.0-4-generic and linux-image-extra-3.11.0-4-generic from Saucy packages repository but the problem persists. When trying: $ xev | sed -n 's/^.*state \([0-9].*\), keycode *\([0-9]\+\) *\(.*\), .*$/keycode \2 = \3, state = \1/p' keycode 36 = (keysym 0xff0d, Return), state = 0x10 keycode 232 = (keysym 0x1008ff03, XF86MonBrightnessDown), state = 0x10 keycode 233 = (keysym 0x1008ff02, XF86MonBrightnessUp), state = 0x10 Event codes appear correctly. And changing: /sys/class/backlight/intel_backlight/brightness changes the brightness of the screen, but pressing the key combination does not. I believe this happens because the key combination is, in fact, changing the value of /sys/class/backlight/acpi_video0/brightness As requested tested with 3.8.13.10-raring and the problem happens with it. I also tested with 3.11.5-saucy and the problem persists.
Can you clarify what graphics your machine has ?
My machine is a Core i7 4700MQ, Haswell chipset (HM 87) with Intel HD 4600 graphics and Optimus capable nVidia GK106M (Geforce GTX 765M). # lspci 00:00.0 Host bridge: Intel Corporation Xeon E3-1200 v3/4th Gen Core Processor DRAM Controller (rev 06) 00:01.0 PCI bridge: Intel Corporation Xeon E3-1200 v3/4th Gen Core Processor PCI Express x16 Controller (rev 06) 00:01.1 PCI bridge: Intel Corporation Xeon E3-1200 v3/4th Gen Core Processor PCI Express x8 Controller (rev 06) 00:02.0 VGA compatible controller: Intel Corporation 4th Gen Core Processor Integrated Graphics Controller (rev 06) 00:03.0 Audio device: Intel Corporation Xeon E3-1200 v3/4th Gen Core Processor HD Audio Controller (rev 06) 00:14.0 USB controller: Intel Corporation 8 Series/C220 Series Chipset Family USB xHCI (rev 04) 00:16.0 Communication controller: Intel Corporation 8 Series/C220 Series Chipset Family MEI Controller #1 (rev 04) 00:1a.0 USB controller: Intel Corporation 8 Series/C220 Series Chipset Family USB EHCI #2 (rev 04) 00:1b.0 Audio device: Intel Corporation 8 Series/C220 Series Chipset High Definition Audio Controller (rev 04) 00:1c.0 PCI bridge: Intel Corporation 8 Series/C220 Series Chipset Family PCI Express Root Port #1 (rev d4) 00:1c.2 PCI bridge: Intel Corporation 8 Series/C220 Series Chipset Family PCI Express Root Port #3 (rev d4) 00:1c.3 PCI bridge: Intel Corporation 8 Series/C220 Series Chipset Family PCI Express Root Port #4 (rev d4) 00:1d.0 USB controller: Intel Corporation 8 Series/C220 Series Chipset Family USB EHCI #1 (rev 04) 00:1f.0 ISA bridge: Intel Corporation HM87 Express LPC Controller (rev 04) 00:1f.2 SATA controller: Intel Corporation 8 Series/C220 Series Chipset Family 6-port SATA Controller 1 [AHCI mode] (rev 04) 00:1f.3 SMBus: Intel Corporation 8 Series/C220 Series Chipset Family SMBus Controller (rev 04) 01:00.0 3D controller: NVIDIA Corporation GK106M [GeForce GTX 765M] (rev ff) 04:00.0 Network controller: Intel Corporation Centrino Advanced-N 6200 (rev 35) 05:00.0 Unassigned class [ff00]: Realtek Semiconductor Co., Ltd. Device 5289 (rev 01) 05:00.2 Ethernet controller: Realtek Semiconductor Co., Ltd. RTL8111/8168/8411 PCI Express Gigabit Ethernet Controller (rev 0a) Thanks,
This is also a problem on a related hardware (also Clevo, dmidecode says it is W65_W670SR). The laptop has both an intel HD Graphics 4600 card an NVidia GeForce GT 750M card. Processor is Intel(R) Core(TM) i7-4702MQ CPU @ 2.20GHz. Tested on Fedora 20 3.11.10-300.fc20.x86_64.
Is that a problem with the kernel (the kernel does provide an interface in /sys that changes the brightness), or is it a problem with the userspace that is not choosing the correct interface?